Hi,

this is my first attempt to write to this mailing list, so if I'm doing something wrong please bear with me.

I've been working with extreme value analysis during my PhD and also in my current job. What we often do is to find signal upcrossings (such as mean and zero upcrossings) and find declustered peaks. That is, find the largest peak between two upcrossings, or the two largest peaks between two upcrossings etc...

I'm proposing to add two new functions to the scipy.signal submodule:

   - find_upcross; takes in signal and returns index of upcrossings wrt user defined upcrossing level

   - find_peaks_dc; takes in signal and returns index of peaks (n largest)

(find_peaks_dc is not necessarly easily incorporated into find_peaks, so it may be cleaner to have a separate function).

Any thought on this?